help me about linked list

i wonder about this problem. cause i'm not sure abuut this...can everyone help me...

21. Compare the worst-case big-O time analysis for these two methods: The remove method for the Sequence that is implemented using an array, and the remove method for the Sequence that is implemented using a linked list.

this is a exercise i have to finish before my next final exam...can U help me...& show me how to learn well data struture & algorithm...this is a difficult subject i have studied at university nowT_T...thx so much...hope to get yur help as soon as possible!!!
nice day